"GSO 25mm extension for RC with 2"" focuser"

RC Telescopes by GSO have a long back focus making this system ideal for the use of off-axis-guiders and / or focal reducers. But in standard use, the long back focus may have problematic side effects: in some applications the focuser must be extended totally and it still needs extension then. You can use this M90x1 extension tube that threads directly on the telescope rear cell, just before the focuser.